The invention relates to wheel lock prevention systems, sometimes called anti-skid systems. It is a common fault of known systems of this type, e.g., that described in the German Offenlegungsschrift No. 2 212 566, that distinct underbraking or overbraking of individual wheels occurs on asymmetric roadbed surfaces and also with unsymmetric vehicle brakes. These conditions then result in unacceptably long braking distances or in very poor lateral guidance.
The idea as to how to control each wheel individually in order to alleviate the known disadvantages mentioned above, has long been sought after, but all such apparatuses entail added effort and expense.